What is preseptal cellulitis?

Preseptal Cellulitis: Definition and Clinical Features

Preseptal cellulitis is an infection confined to the eyelids and soft tissues anterior to the orbital septum, characterized by eyelid erythema, edema, warmth, and tenderness without affecting extraocular movements or vision. 1

Clinical Presentation

Preseptal cellulitis presents with distinctive features:

• Eyelid erythema, edema, warmth, and tenderness
• Skin may appear dimpled like an orange peel (peau d'orange)
• Possible periorbital vesicles or bullae
• Potential cutaneous hemorrhage (petechiae or ecchymoses)
• Possible lymphangitis and regional lymph node inflammation
• Occasionally, systemic symptoms like tachycardia, confusion, or leukocytosis 1

Distinguishing from Orbital Cellulitis

Differentiating preseptal from orbital cellulitis is crucial as the latter can lead to vision-threatening complications:

• Preseptal cellulitis: Infection anterior to orbital septum, normal extraocular movements, no vision changes, no proptosis
• Orbital cellulitis: Infection posterior to orbital septum, with:
  • Pain with eye movements
  • Restricted eye movements/diplopia
  • Proptosis
  • Vision changes 1, 2

Diagnostic Features

Key clinical differences between preseptal and orbital cellulitis include:

• Age: Preseptal cellulitis tends to affect younger children (mean age 3.9 years vs. 7.5 years for orbital cellulitis) 3
• Fever: Less common in preseptal (51.5%) vs. orbital cellulitis (82.2%) 3
• Preexisting sinusitis: Rare in preseptal (2%) vs. common in orbital cellulitis (77.8%) 3
• Laboratory markers: C-reactive protein levels are significantly lower in preseptal cellulitis (median 17.85 mg/L vs. 136.35 mg/L in orbital cellulitis) 3

Etiology and Risk Factors

Common predisposing factors include:

• In children: Skin lesions, trauma, insect bites
• In adults: Dacryocystitis
• Sinusitis (more commonly leads to orbital rather than preseptal cellulitis)
• Staphylococcus aureus is the most commonly isolated pathogen 4

Imaging

• Imaging is not routinely required for typical preseptal cellulitis
• CT orbits with IV contrast is indicated when:
  • Clinical findings are insufficient to distinguish from orbital cellulitis
  • Poor response to initial therapy
  • Suspicion of abscess formation or deeper infection 1

Warning Signs Requiring Urgent Referral

Immediate ophthalmology referral is needed if any of these are present:

• Pain with eye movements
• Movement restriction/diplopia
• Proptosis
• Vision changes 1

Clinical Pitfalls

• Misdiagnosing orbital cellulitis as preseptal cellulitis can lead to vision-threatening complications
• Clinical findings alone may not be specific enough to distinguish between the two in all cases
• Puffy eyelids may indicate early preseptal cellulitis, which requires prompt treatment to prevent progression 1
• Despite historically significant morbidity, early diagnosis and prompt treatment with appropriate antibiotics and/or surgical intervention typically leads to good outcomes 4